The Blue Jays optioned Kay (lower leg) to their alternate training site Thursday.
Kay exited his final Grapefruit League appearance Saturday with a lower right leg contusion, but he said he was fine after the appearance. Rather than any concern about Kay's health, Toronto excluded the southpaw from its Opening Day roster because he was on the losing end of a job battle with T.J. Zeuch, who is expected to temporarily fill in as the team's No. 5 starter while Robbie Ray (elbow) is on the mend.